diff --git a/contracts/Bounty.sol b/contracts/Bounty.sol
index 46699b1b3..a90d2e44a 100644
--- a/contracts/Bounty.sol
+++ b/contracts/Bounty.sol
@@ -1,8 +1,8 @@
 pragma solidity ^0.4.4;
 
 
-import './PullPayment.sol';
-import './Killable.sol';
+import './payment/PullPayment.sol';
+import './lifecycle/Killable.sol';
 
 
 /*
diff --git a/contracts/DayLimit.sol b/contracts/DayLimit.sol
index 41f9e4994..8fd07255b 100644
--- a/contracts/DayLimit.sol
+++ b/contracts/DayLimit.sol
@@ -1,7 +1,7 @@
 pragma solidity ^0.4.4;
 
 
-import './Shareable.sol';
+import './ownership/Shareable.sol';
 
 
 /*
diff --git a/contracts/MultisigWallet.sol b/contracts/MultisigWallet.sol
index 867de28ff..245ae3e1a 100644
--- a/contracts/MultisigWallet.sol
+++ b/contracts/MultisigWallet.sol
@@ -1,8 +1,8 @@
 pragma solidity ^0.4.4;
 
 
-import "./Multisig.sol";
-import "./Shareable.sol";
+import "./ownership/Multisig.sol";
+import "./ownership/Shareable.sol";
 import "./DayLimit.sol";
 
 
diff --git a/contracts/examples/BadArrayUse.sol b/contracts/examples/BadArrayUse.sol
deleted file mode 100644
index dd8a65344..000000000
--- a/contracts/examples/BadArrayUse.sol
+++ /dev/null
@@ -1,23 +0,0 @@
-pragma solidity ^0.4.4;
-
-
-import '../PullPayment.sol';
-
-
-// UNSAFE CODE, DO NOT USE!
-contract BadArrayUse is PullPayment {
-  address[] employees;
-
-  function payBonus() {
-    for (var i = 0; i < employees.length; i++) {
-			address employee = employees[i];
-			uint bonus = calculateBonus(employee);
-    	asyncSend(employee, bonus);
-    }
-  }
-
-	function calculateBonus(address employee) returns (uint) {
-    // some expensive computation...
-  }
-
-}
diff --git a/contracts/examples/BadFailEarly.sol b/contracts/examples/BadFailEarly.sol
deleted file mode 100644
index ee26bdd1d..000000000
--- a/contracts/examples/BadFailEarly.sol
+++ /dev/null
@@ -1,17 +0,0 @@
-pragma solidity ^0.4.4;
-
-
-// UNSAFE CODE, DO NOT USE!
-contract BadFailEarly {
-
-  uint constant DEFAULT_SALARY = 50000;
-  mapping(string => uint) nameToSalary;
-
-  function getSalary(string name) constant returns (uint) {
-    if (bytes(name).length != 0 && nameToSalary[name] != 0) {
-      return nameToSalary[name];
-    } else {
-      return DEFAULT_SALARY;
-    }
-  }
-}
diff --git a/contracts/examples/BadPushPayments.sol b/contracts/examples/BadPushPayments.sol
deleted file mode 100644
index 7bc11c665..000000000
--- a/contracts/examples/BadPushPayments.sol
+++ /dev/null
@@ -1,23 +0,0 @@
-pragma solidity ^0.4.4;
-
-
-// UNSAFE CODE, DO NOT USE!
-contract BadPushPayments {
-
-	address highestBidder;
-	uint highestBid;
-
-	function bid() payable {
-		if (msg.value < highestBid) throw;
-
-		if (highestBidder != 0) {
-      // return bid to previous winner
-			if (!highestBidder.send(highestBid)) {
-        throw;
-      }
-		}
-
-	  highestBidder = msg.sender;
-	  highestBid = msg.value;
-	}
-}
diff --git a/contracts/examples/GoodArrayUse.sol b/contracts/examples/GoodArrayUse.sol
deleted file mode 100644
index 8995702a8..000000000
--- a/contracts/examples/GoodArrayUse.sol
+++ /dev/null
@@ -1,25 +0,0 @@
-pragma solidity ^0.4.4;
-
-
-import '../PullPayment.sol';
-
-
-contract GoodArrayUse is PullPayment {
-  address[] employees;
-  mapping(address => uint) bonuses;
-
-  function payBonus() {
-    for (uint i = 0; i < employees.length; i++) {
-			address employee = employees[i];
-			uint bonus = bonuses[employee];
-    	asyncSend(employee, bonus);
-    }
-  }
-
-	function calculateBonus(address employee) returns (uint) {
-    uint bonus = 0;
-    // some expensive computation...
-    bonuses[employee] = bonus;
-  }
-
-}
diff --git a/contracts/examples/GoodFailEarly.sol b/contracts/examples/GoodFailEarly.sol
deleted file mode 100644
index dce0eac44..000000000
--- a/contracts/examples/GoodFailEarly.sol
+++ /dev/null
@@ -1,15 +0,0 @@
-pragma solidity ^0.4.4;
-
-
-contract GoodFailEarly {
-
-  uint constant DEFAULT_SALARY = 50000;
-  mapping(string => uint) nameToSalary;
-
-  function getSalary(string name) constant returns (uint) {
-    if (bytes(name).length == 0) throw;
-    if (nameToSalary[name] == 0) throw;
-
-    return nameToSalary[name];
-  }
-}
diff --git a/contracts/examples/GoodPullPayments.sol b/contracts/examples/GoodPullPayments.sol
deleted file mode 100644
index fc0cd986b..000000000
--- a/contracts/examples/GoodPullPayments.sol
+++ /dev/null
@@ -1,27 +0,0 @@
-pragma solidity ^0.4.4;
-
-
-contract GoodPullPayments {
-  address highestBidder;
-  uint highestBid;
-  mapping(address => uint) refunds;
-
-  function bid() external payable {
-    if (msg.value < highestBid) throw;
-
-    if (highestBidder != 0) {
-      refunds[highestBidder] += highestBid;
-    }
-
-    highestBidder = msg.sender;
-    highestBid = msg.value;
-  }
-
-  function withdrawBid() external {
-    uint refund = refunds[msg.sender];
-    refunds[msg.sender] = 0;
-    if (!msg.sender.send(refund)) {
-      refunds[msg.sender] = refund;
-    }
-  }
-}
diff --git a/contracts/examples/ProofOfExistence.sol b/contracts/examples/ProofOfExistence.sol
deleted file mode 100644
index 0bf7ca220..000000000
--- a/contracts/examples/ProofOfExistence.sol
+++ /dev/null
@@ -1,38 +0,0 @@
-pragma solidity ^0.4.4;
-
-
-/*
- * Proof of Existence example contract
- * see https://medium.com/zeppelin-blog/the-hitchhikers-guide-to-smart-contracts-in-ethereum-848f08001f05
- */
-contract ProofOfExistence {
-
-  mapping (bytes32 => bool) public proofs;
-
-  // store a proof of existence in the contract state
-  function storeProof(bytes32 proof) {
-    proofs[proof] = true;
-  }
-
-  // calculate and store the proof for a document
-  function notarize(string document) {
-    var proof = calculateProof(document);
-    storeProof(proof);
-  }
-
-  // helper function to get a document's sha256
-  function calculateProof(string document) constant returns (bytes32) {
-    return sha256(document);
-  }
-
-  // check if a document has been notarized
-  function checkDocument(string document) constant returns (bool) {
-    var proof = calculateProof(document);
-    return hasProof(proof);
-  }
-
-  // returns true if proof is stored
-  function hasProof(bytes32 proof) constant returns (bool) {
-    return proofs[proof];
-  }
-}
diff --git a/contracts/examples/PullPaymentBid.sol b/contracts/examples/PullPaymentBid.sol
deleted file mode 100644
index 8ba51422f..000000000
--- a/contracts/examples/PullPaymentBid.sol
+++ /dev/null
@@ -1,20 +0,0 @@
-pragma solidity ^0.4.4;
-
-
-import '../PullPayment.sol';
-
-
-contract PullPaymentBid is PullPayment {
-  address public highestBidder;
-  uint public highestBid;
-  
-  function bid() external payable {
-    if (msg.value <= highestBid) throw;
-    
-    if (highestBidder != 0) {
-      asyncSend(highestBidder, highestBid);
-    }
-    highestBidder = msg.sender;
-    highestBid = msg.value;
-  }
-}
diff --git a/contracts/examples/StoppableBid.sol b/contracts/examples/StoppableBid.sol
deleted file mode 100644
index 53e1aebdc..000000000
--- a/contracts/examples/StoppableBid.sol
+++ /dev/null
@@ -1,26 +0,0 @@
-pragma solidity ^0.4.4;
-
-
-import '../PullPayment.sol';
-import '../Stoppable.sol';
-
-
-contract StoppableBid is Stoppable, PullPayment {
-  address public highestBidder;
-  uint public highestBid;
-
-  function bid() external payable stopInEmergency {
-    if (msg.value <= highestBid) throw;
-    
-    if (highestBidder != 0) {
-      asyncSend(highestBidder, highestBid);
-    }
-    highestBidder = msg.sender;
-    highestBid = msg.value;
-  }
-
-  function withdraw() onlyInEmergency {
-    selfdestruct(owner);
-  }
-
-}
diff --git a/contracts/Killable.sol b/contracts/lifecycle/Killable.sol
similarity index 86%
rename from contracts/Killable.sol
rename to contracts/lifecycle/Killable.sol
index 10621d63e..7ec3e2b51 100644
--- a/contracts/Killable.sol
+++ b/contracts/lifecycle/Killable.sol
@@ -1,7 +1,7 @@
 pragma solidity ^0.4.4;
 
 
-import "./Ownable.sol";
+import "../ownership/Ownable.sol";
 
 
 /*
diff --git a/contracts/Migrations.sol b/contracts/lifecycle/Migrations.sol
similarity index 91%
rename from contracts/Migrations.sol
rename to contracts/lifecycle/Migrations.sol
index 010f551fc..8b981e774 100644
--- a/contracts/Migrations.sol
+++ b/contracts/lifecycle/Migrations.sol
@@ -1,7 +1,7 @@
 pragma solidity ^0.4.4;
 
 
-import './Ownable.sol';
+import '../ownership/Ownable.sol';
 
 
 contract Migrations is Ownable {
diff --git a/contracts/Stoppable.sol b/contracts/lifecycle/Stoppable.sol
similarity index 94%
rename from contracts/Stoppable.sol
rename to contracts/lifecycle/Stoppable.sol
index 5c018844a..2dc37d6fc 100644
--- a/contracts/Stoppable.sol
+++ b/contracts/lifecycle/Stoppable.sol
@@ -1,7 +1,7 @@
 pragma solidity ^0.4.4;
 
 
-import "./Ownable.sol";
+import "../ownership/Ownable.sol";
 
 
 /*
diff --git a/contracts/Claimable.sol b/contracts/ownership/Claimable.sol
similarity index 100%
rename from contracts/Claimable.sol
rename to contracts/ownership/Claimable.sol
diff --git a/contracts/DelayedClaimable.sol b/contracts/ownership/DelayedClaimable.sol
similarity index 100%
rename from contracts/DelayedClaimable.sol
rename to contracts/ownership/DelayedClaimable.sol
diff --git a/contracts/Multisig.sol b/contracts/ownership/Multisig.sol
similarity index 100%
rename from contracts/Multisig.sol
rename to contracts/ownership/Multisig.sol
diff --git a/contracts/Ownable.sol b/contracts/ownership/Ownable.sol
similarity index 100%
rename from contracts/Ownable.sol
rename to contracts/ownership/Ownable.sol
diff --git a/contracts/Shareable.sol b/contracts/ownership/Shareable.sol
similarity index 100%
rename from contracts/Shareable.sol
rename to contracts/ownership/Shareable.sol
diff --git a/contracts/PullPayment.sol b/contracts/payment/PullPayment.sol
similarity index 100%
rename from contracts/PullPayment.sol
rename to contracts/payment/PullPayment.sol
diff --git a/contracts/test-helpers/PullPaymentMock.sol b/contracts/test-helpers/PullPaymentMock.sol
index 2d6ca1e2f..223f8d0d1 100644
--- a/contracts/test-helpers/PullPaymentMock.sol
+++ b/contracts/test-helpers/PullPaymentMock.sol
@@ -1,7 +1,7 @@
 pragma solidity ^0.4.4;
 
 
-import '../PullPayment.sol';
+import '../payment/PullPayment.sol';
 
 
 // mock class using PullPayment
diff --git a/contracts/test-helpers/ShareableMock.sol b/contracts/test-helpers/ShareableMock.sol
index ebf06546e..0d30958af 100644
--- a/contracts/test-helpers/ShareableMock.sol
+++ b/contracts/test-helpers/ShareableMock.sol
@@ -1,5 +1,5 @@
 pragma solidity ^0.4.4;
-import "../Shareable.sol";
+import "../ownership/Shareable.sol";
 
 contract ShareableMock is Shareable {
 
diff --git a/contracts/test-helpers/StoppableMock.sol b/contracts/test-helpers/StoppableMock.sol
index 44c12bbcf..32e456a20 100644
--- a/contracts/test-helpers/StoppableMock.sol
+++ b/contracts/test-helpers/StoppableMock.sol
@@ -1,7 +1,7 @@
 pragma solidity ^0.4.4;
 
 
-import '../Stoppable.sol';
+import '../lifecycle/Stoppable.sol';
 
 
 // mock class using Stoppable